The present invention relates to switches having a knob rotatable by the user for switching between a plurality of desired control positions for controlling the operation of an electrically operated appliance. The invention relates particularly to rotary switches of the type intended for switching loads such as motors operating on relatively low voltage direct current supplies as, for example, a 12-volt supply typically encountered on board automobiles.
In automotive selector or control switch applications, it has been desired to provide a user control knob actuator which is readily and easily rotatable between a plurality of control positions, and to provide for detented action in each of the desired control positions, and also to provide for illumination of indicia indicating the state of switch actuation and the control function selected at each position to facilitate nighttime operation.
Furthermore, it is often required to switch substantial current as, for example, 20 amps motor load at 12-volt DC, which is typical of starting currents in an automobile passenger compartment climate control blower motor. Thus it has been desired to provide an illuminated reliable low cost rotary selector switch for relatively high current, low voltage applications such as those encountered in automobiles, and to provide such a switch which is capable of high volume mass production, which is reliable in service, and which is low in manufacturing cost.